Allergy最新文献

Background: In Europe, Omalizumab (anti-IgE) is indicated for the treatment of moderate to severe asthma, but not for IgE-mediated food allergy (FA).

Objective: We assessed the impact of Omalizumab on efficacy, safety, and quality of life (FA-QoL) in patients with moderate to severe asthma and who have a history of anaphylaxis to peanut, tree nuts, fish, egg, milk, and/or wheat.

Methods: Food-allergic children (6-18 years) with moderate to severe asthma underwent oral food challenges (OFCs) to establish the threshold of reaction to the culprit food(s) at baseline (T0) and at 4-month intervals (T1, T2, and T3) during their first year of treatment with Omalizumab. We recorded the number and severity of food-allergic reactions, Asthma Control Test (ACT) scores, FA-QoL, and total IgE levels.

Results: In 65 patients allergic to 107 foods, the No Observed Adverse Events Level (NOAEL) at T1 increased: 243- and 488-fold for fresh and baked milk, respectively; 172- and 134-fold for raw and baked egg; 245-fold for hazelnut; 55-fold for peanut; 31-fold for wheat; and 10-fold for fish. Full tolerance was achieved in 66.4% of OFCs at T1, 58.3% at T2, and 75% at T3. Ninety-five foods were liberalized in the diet of 55 patients; the remaining 12 were introduced by 10 patients at least in traces. Throughout the study, 40 out of 65 were able to get a free diet. ACT increased from 17 (Q1-Q3: 15-17) to 23.6 (Q1-Q3: 23-25). The FA-QoL score in children ≤12 years decreased from 4.63 ± 0.74 to 2.02 ± 1.13, and in adolescents from 4.68 ± 0.92 to 1.90 ± 1.50.

Conclusions: During Omalizumab therapy, a safe reintroduction of allergenic foods is feasible.

Trial registration number: ClinicalTrials.gov, NCT06316414.

Background: Reasons for Th2 skewing in IgE-mediated food allergies remains unclear. Clinical observations suggest impaired T cell activation may drive Th2 responses evidenced by increased atopic manifestations in liver transplant patients on tacrolimus (a calcineurin inhibitor). We aimed to assess differentiation potential, T cell activation and calcium influx of naïve CD4⁺ T cells in children with IgE-mediated food allergies.

Methods: Peripheral blood mononuclear cells from infants in the Starting Time for Egg Protein (STEP) Trial were analyzed by flow cytometry to assess Th1/Th2/Treg development. Naïve CD4⁺ T cells from children with and without food allergies were stimulated for 7 days to assess Th1/Th2/Treg transcriptional factors and cytokines. Store operated calcium entry (SOCE) was measured in children with and without food allergies. The effect of tacrolimus on CD4⁺ T cell differentiation was assessed by treating stimulated naïve CD4⁺ T cells from healthy volunteers with tacrolimus for 7 days.

Results: Egg allergic infants had impaired development of IFNγ⁺ Th1 cells and FoxP3⁺ transitional CD4⁺ T cells compared with non-allergic infants. This parallels reduced T-bet, IFNγ and FoxP3 expression in naïve CD4⁺ T cells from food allergic children after in vitro culture. SOCE of naïve CD4⁺ T cells was impaired in food allergic children. Naïve CD4⁺ T cells treated with tacrolimus had reduced IFNγ, T-bet, and FoxP3, but preserved IL-4 expression.

Conclusions: In children with IgE-mediated food allergies, dysregulation of T helper cell development is associated with impaired SOCE, which underlies an intrinsic impairment in Th1 and Treg differentiation. Along with tacrolimus-induced Th2 skewing, this highlights an important role of SOCE/calcineurin pathway in T helper cell differentiation.

Background: Tryptase, a mast cell protease, has been identified as a potential therapeutic target in managing patients with refractory asthma. We assessed the efficacy, safety, pharmacokinetics, and pharmacodynamics of MTPS9579A, an anti-tryptase antibody, in a phase 2a randomized trial for patients with uncontrolled asthma and a phase 1c trial to understand activity within the lower respiratory tract.

Methods: Phase 2a patients (n = 134) received 1800 mg MTPS9579A or placebo intravenously every 4 weeks for 48 weeks. The primary endpoint was time to the first composite exacerbation event. Phase 1c patients (n = 27) received one intravenous dose of 300 or 1800 mg MTPS9579A or placebo. Both trials measured MTPS9579A concentrations and effects on tryptase in serum and nasal lining fluid; phase 1c also analyzed bronchial lining fluid.

Results: MTPS9579A did not meet the primary endpoint (hazard ratio = 0.90; 95% CI: 0.55-1.47; p = 0.6835); exacerbation rates in the placebo group were low. Serum and nasal MTPS9579A pharmacokinetics and tryptase levels were consistent with data from healthy volunteers. However, in phase 1c patients, compared to nasal levels, MTPS9579A bronchial concentrations were 6.8-fold lower, and bronchial active and total tryptase levels were higher (119-fold and 30-fold, respectively). Pharmacokinetic/pharmacodynamic modeling predicted intravenous doses of 3800 mg every 4 weeks would be necessary to achieve 95% active tryptase inhibition from baseline.

Conclusions: The MTPS9579A dose tested in the phase 2a study was insufficient to inhibit tryptase in bronchial lining fluid, likely contributing to the observed lack of efficacy.